Rotary valve.



H. E. COFFIN.

ROTARY VALVE. APPLICATION FILED FEB. 4. I9II.

Patented Jan. 18, 1916.

2 SHEETS-SHEET l.

Wf/MSS @5^ ffm@ far /f I am/Va. @ffm n' j v H. E. COFFIN.

ROTARY VALVE. f

Patented Jan. 18, 1916.

2 SHEETS-SHEET 2 gays es' f W@ 'UNITED4 sTA s PANT OFFICE.

HOWARD n. corrIN,'or DETROIT, MICHIGAN, AssIGNoH, BY MEsNE ASSIGNMENTS, To

THE DETHoIT MOTOR sa MACHINE COMPANY, or DETROIT, MICHIGAN, A ooHIoHA- TION 0F MICHIGAN.

ROTARY VALVE.

Specification of Letters Yatent.

Application led February 4, 1911. Seria1.No. 606,531.

To all whom it may concern Be it known that I, HOWARD E. COFFIN, a citizen of the United States of America, residing `at Detroit, in the county of Wayne and vState of Michigan, have` invented certain new and usefullmprovements in Rotary-Valve Construction, of which the lfollowing is a speciiication, reference being had'y therein to the accompanying drawings.

The invention relates to rotary valves particularly designed for use in connection with explosion engines, and the invention consists in certain features of construction as herein after set forth. e,

ln the drawings, Figure 1 is a vertical central section through a/portion ,of the engine casing showing the valve construction; Fig. 2 is a sectional perspective view thereof. Fig. 3 is a view similar to Fig. 1 showing a modified construction; Fig. 4 shows still another modication.

My improved valve belongs to the disk type and is preferably arranged inthe head of the engine cylinder, andis operated by a rotary stem passing out through the head of the cylinder. With such a construction the lower face of the valve is exposed to the pressure developed within the cylinder in the explosion of the gases which force it out ward against the lvalve seat-and greatly increases the frictional resistance to rotation.

It is one of the objects of the present invention to reduce the friction and the wear of the seat and valve disk'by providing a thrust bearing which will holdthese partsv slightly separated..

It'is a further object to provide means for adjusting this thrust bearing to vary the distance of the valve from its seat, and still an? other object is to provide'means for yieldfl ably drawing the disk to its seat. f

yIn detail7 A is the engine cylinder which as shown' has a counterbore B at its upper end in which is placed 4the disk valve C, and D is the'he'ad of thecylinder against which the disk isseated. I E is the rotary stem for the valve which extends outward through the bearing F in K the head, preferably surrounded by a water jacket. Gr, and at its upper end has mounted thereon a gear wheel H. This gear wheel` forms the driver for the lvalve and is operated by a suitable train of gearing v( not shown) from the crank shaft of.theeng1ne..

f therefore provide a bearing I for takng'the,

With the construction as thus fanfde-V scribed the pressure developed within the engine cylinder will force the disk upward against its seat, while the suction in thehyl# inder will tend to draw the disk awayfrom its seat. The combined action' will cause a` hammering ofthe valve on its seat which is" detrimental, while the pressure during l.the

, explosion and compresslon strokes of engine increase the frictional resista11 e:.{ I

thrust of the valve which is preferably lol4E cated in an enlargment I of the bearing F for the stem. As shown, the bearinglr is formed by balls I2 between races I3 and?, the former .bearing againsta shoulder'. J upon the valve stem. i

I K is m1 dlllmlolev seat 'for the ball-raced.

which preferably has a threaded Aengagement with a flange L on the casing and isarranged to surround the hub H of the gear Patented' Jan. 18,1916.

wheel H. Thus by adjusting the member `the' position of thev ballrace I isshifted,

which causes a corresponding adjustment of the stem' E and disk C.

The gear wheel H is preferably feathered, as indicated at M tothe rotary stem Eso as to permit an independent longitudinal movement of said stem.. This will allow the disk and stem tomove inward,` and to prevent such a result during the suction stroke of the/engine, a sprlng or other resilient -yieldable means is employed for drawing 'the disk upward. This preferably'consists.`

of a spring washer N which. is arranged to bear upon the gear wheel H and centraliy engages a pin O in thevalve stem. The'ar'- rangement is such that the spring is n0r- I mally under slight tension and willact to draw the valve.to its seat but will-yield' to prevent any binding.

, With the construction as described, in use" the valve when first positioned mayjbeslightly spaced from its seathor if desired may be tight against the seat-so as td permit grinding of the surfaces @into 'perfect' ffonaA tact. In each case the thrust bearing will" Ioo limit the longitudinal movement of the .valve l stem and on account of the ballsllandwthe' vslight radial distance from the axis'will ref .i

duce the friction. Where the valvef is full contactv with ythe seat. it lwill soonwearso as to be separated th'erefrdm*and-1the.

thrust bearing will then prevent for adjusting the thrust bearing tovary the adjustable means engging said .stem for distance of the valve from its seat. variably relieving the loadvfrom said seat. 10

12. The combination ,with a rotary valve In testimony whereof I Y. gtx my .signaand its seat, cfa,v stem for said valve, and ture in presence off/two Witnesses. ,lmeans engaging said stem for relieving the HOWARD E. COFFIN.

' load from said seat. V/'itnesseszl 13. The combination with a, rotary valve L. M.' CARLE, and its seat,' of atv stem for said valve, and J. Gr. VINCENT. 

